The United States Postal Service (U.S.P.S.) increasingly uses automated, computer-controlled machinery to sort mail more efficiently. Two vital machines are the optical character reader (OCR) and the wide-area bar code reader (WABCR). These machines can recognize reliably and speedily the numeric information, specifically postal bar codes, on pieces of mail. The bar codes are converted into numeric destination data for high-speed sorting, benefiting both the U.S.P.S. and the postal customers.
The bar code can be applied to the envelope by the customer or by the U.S.P.S. The U.S.P.S. uses the OCR for this purpose. The OCR scans the address and converts it into a bar code, which it prints on the envelope. If the customer applies the bar code, mail-processing is accelerated because the OCR can be bypassed. The envelope goes directly to the WABCR for sorting.
FIG. 1 shows schematically the respective paths for coded and uncoded pieces of mail. Uncoded envelope 10 passes through OCR 20, which scans its address 30. OCR 20 then prints bar code 40 on envelope 10, which proceeds through WABCR 50 to await delivery, as indicated at block 60. Coded envelope 11, already printed with bar code 40, bypasses OCR 20 and proceeds directly to WABCR 50.
The U.S.P.S. encourages its business customers to apply their own bar codes. This saves money for the U.S.P.S. and the customers, and speeds mail delivery. See, for example, Publication 67 of the United States U.S.P.S., "Automation Plan for Business Mailers," October 1989. The use of OCR to read and interpret printed addresses on mail can result in errors due to illegible print or unrecognizable fonts, and OCR cannot currently be used with a high degree of reliability for handwritten addresses. If an envelope, label, flat or package cannot be read using OCR, then it generally has to be diverted to manual sorting or a non-automated piece of equipment which is more labor intensive.
The U.S.P.S.'s OCR and WABCR equipment are programmed to recognize POSTNET bar codes. The POSTNET bar code is a unique bar code system used by the U.S.P.S. It symbolizes a destination ZIP Code through a combination of tall and short bars. The complex symbology of the POSTNET bar code will be explained further herein.
There is existing electronic equipment which can access a database of addresses to print the addresses with POSTNET bar codes on envelopes. This sophisticated equipment is, however, beyond the means of many small businesses. The present invention provides a convenient, effective, and inexpensive way of applying the bar code before mailing. It can also effectively be used by non-business customers.